It is well known that the dazzling of drivers of vehicles, either in the daytime by the sun or especially at night by oncoming headlights, creates actual temporary blindness and is the cause of numerous and serious traffic accidents.
In order to attempt to overcome these disadvantages, various systems have been proposed, either built into the vehicle itself (movable sun visors, tinted windshields, adjustable rearview mirrors) or designed for the driver (sun glasses, special night glasses, filter lenses). Unfortunately, these systems are not very effective. For example, the sun visor system, or the classic visor, only protects the eyes in a horizontal plane; as a result, when the sun is very low on the horizon or when the headlights of a vehicle coming in the opposite direction are dazzling, these systems cannot protect the driver's eyes without obstructing his view of the road. In addition, the mobility of sun visors is not always satisfactory and the curvature and contour of the highway requires difficult and dangerous maneuvers which do not eliminate the sudden dazzle which often happens when rounding a corner. Tinted windshields or special glasses, besides their additional cost (high cost), have the disadvantages of being poorly adaptable to the user, and cannot be adjusted as a function of brightness, and in many instances themselves constitute additional causes of danger by a permanent reduction of the field of vision or of brightness.